In the context of Kapteyn's plan to obtain a photometric standard, in
Potsdam more than 400 photographic plates of several Selected Areas,
Special Areas, and Kapteyn-Pritchard areas were obtained between 1910 and
1933, both as direct images and with an object prism. This service
provides FITS images of the science area of the plates as well as images of
the entire plates, including previous markings.
The Wide-Field Plate Database (WFPDB_) contains the descriptive information
for the astronomical wide-field (>1°) photographic observations stored in
numerous archives all over the world. The total number of these
observations, obtained since the end of the 19th century with more
then 200 instruments (telescopes) is about 2 550 000 from 509 archives.
The WFPDB is continually being updated, providing currently access to the
information for about 640 000 plates from 117 plate archives (30% of the
estimated total number of wide-field plates)
.. _WFPDB: http://www.skyarchive.org/
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